Stud driving tool



n3fm- 26, 1954 v. a ERlcKsoN STUD DRIVING TooL Filed March 2, 1951 Patented Jan. 26, 1954 UNITED STATES EATENT OFFICE STUD DRIVING TOOL Application March 2, 1951, Serial No. 213,549

The Apresent invention relates to stud driving tools of the type employed for the explosive installation or studs in various types oi concrete and steel structures. and is concerned more particularly with apparatus adapted to employ a standard explosive charge and vary the effective force of such charge as applied to the stud to obtain the proper force for successful installation oi a particular stud in a particular wall surface. This invention is concerned with power control method and apparatus of the general character disclosed and claimed in the copending application oi Erickson and Bullwinkle, Serial No. 135,744 led December 29, 1949, for Stud Driving rI'ool.

The present invention provides for varying of the combustion space or chamber for the explosive charge and also for simultaneously varying the spacing from the muzzle end of the barrel to influence further the energy imparted to the stud. The invention employs an insert in the barrel of the tool which is formed to provide for rictional retention of the stud at any desired location along the insert length.

The above and other objects of the invention are attained in connection with a preferred ernbodiment of the invention, as disclosed and described in connection with the accompanying drawing, in which;

Figure l is an elevational View of a stud driving tool with certain parts broken away and shown in section to illustrate the combustion chamber of the tool.

Figure 2 is an enlarged View of a portion of Figure l,

Figure 3 is a fragmentary enlarged view showing a stud held in place in the sleeve insert.

Figur@ 4 is a fragmentary perspective View of the sleeve insert.

Referring to Figure 1 there is shown a stud driving tool of the character described and claimed in the accompanying application of Smith and Daugherty, Serial No. 124,078, filed October 28, 1949, for Stud Driving Tool and Erickson and Bullwinkle, Serial No. i30,8l8 filed Decernber 2, 1949, for Stud Driving` Tool. In general, stud driving tools of this character are adapted to be separated or broken in two halves including a rear part Ill which contains the various ring control parts, including, for example, a iiring pin carrier Il, and a front or barrel part I2 of the tool in which the barrel I3 is included. The barrel I3 is provided with an enlarged rear end ISA which has a threaded connection Within the of the ring pin carrier II to connect the two halves in the tool. Barrel I3 is also provided with 7 Claims. (Cl. 1--44.5)

an enlarged bore in which a combustion chamber or breech plug insert I/I is provided for holding the cartridge I8 containing a standard explosive charge. Immediately adjacent the enlarged. bore, a smaller enlargement of the bore extends down the barrel to receive a sleeve insert I9 which has a slight press t therein to maintain its position.

The sleeve insert I9 has a plurality of holding fingers for a stud I5 and these iingers are formed by a series of equally spaced spring members IQA which are struck out or formed in the wall of the tube I9. As shown there are two series of spring members ISA, providing respective lingers by which a stud may be frictionally held as shown in Figure 3, for example, where the stud has compressed a sleeve spring ISA. It will be noted that the spring iingers I 9A of the two series are oiset longitudinally of the sleeve to provide for retention of the stud at any desired location. The internal diameter of the sleeve retains the stud in axial alignment Within the barrel.

In operation, the tool is broken in two halves by unthreading the barrel I3 from the firing pin carrier I I and withdrawing the barrel from within the rear part I B. With the parts disassembled, the breech plug or insert I4 is removed and the stud I5 is installed in the sleeve I9 in engagement with the desired finger ISA. The,I stud may be positioned as disclosed in said application Serial No. 135,744. The cartridge I8 is placed in the breech plug I4, and the parts are reassembled as shown in Figure 1 for firing operation.

Firing is accomplished by placing the end of the barrel I3 against the surface in to which the stud is to be driven, and by pressing or telescoping the barrel I2 and iiring pin carrier II back into the remainder of the tool until the ring position is reached, as disclosed in said applications, and then turning the rear end grip 2I with respect to the central housing 22 to lire the tool. At this time the deector pad structure 23 mounted about the barrel I3 is enga-ged with the surface about the area of engagement of the end of the barrel so as to provide protection from iiying particles of the wall surface upon explosive installation of stud.

As previously stated, the effective force of the standard explosive charge is varied by positioning the stud at diierent pre-determined distances along the barrel and in spaced relation with respect to the muzzle end of the barrel and with respect to the cartridge. In this way the volume of the combustion chamber is varied, and the effective length of the barrel thru which a stud is driven by the explosive charge is also changed, and these two factors are combined in varying the power control to drive the stud.

While I have shown a preferred form of the invention, it is apparent that the invention can be employed in other Ways so that its scope should be limited only by the scope of the claims appended hereto.

I claim:

l. In a stud-driving tooLeaubarrLel :havingA a longitudinal bore therein enlarged at one end, a breech plug insert mounted in the enlarged portion of said bore, means in said breech plug for holding a cartridge, a sleeve memben'ismeans for seating said sleeve member in saidbarrel 5 spaced circumferentially with respect to each other.

5. A stud driving tool as recited in claim 3, in `which,saidrictional retaining .means comprises vv'aflongitu'dinally disposed'; series :fof l.leaf spring members.

6. A stud driving tool as recited in claim 3,

in which said frictional retaining means comprisesalongitudinal series of obstructions mounted.for,movement in,said barrel and transversely adjacent said breech plug *"insert, said ""sleevedsth'ereof,.leach .obstruction being normally in an member having a series `fspring A`members".` for holding a stud in spaced relation to a cartridge in said breech plug insert.

2. In a stud driving tool, a barrel.. having Ya. longitudinal bore therein enlarged atone end, a breech plug insert mounted in the enlarged portionr `f said bore; and'A a "sleeve member seated saidbarrel adjacent said breech' plug-insert having friction felements falong its'length'` for holding a stud in position.

"3. In a stud driving Itool, a'vbarr'elhaving *mounting* means atV its breech end for acartridge, and :Erictionaly retaining means mount-'edi-insa'id barrel as apart of the bore'thereof and extending longitudinally of said' barrel adjacent said breech end'for holding a'std 'in anyV one f f a `A plurality of desired 'seleetedf positions with respect -to `the cartridge.

.'ob'st'ructinggposition Within the bore of the barrel, and being movable by a stud to withdrawn positionr'witlrvrespect to the bore.

7..In.. a stud driving tool, a barrel having a `longitudinal bore therein enlarged at one end, a

breech plug insert for'mounting in the enlarged A*portion'of'said' bore, and stud retainingmeans v'mounted in said barrel adjacent 'saidbreechtplug v'insert comprising a longitudinal series of obstructions Vmounted for yielding 'movementtrans- `vers'ely ofthe' barrel.

VIRGINIUS'R. ERICKSON.

'References' Cited vinithelef :this patent .UNTED STATES'PATENTS yNumber .Name l Date 42,359,515 `Fanger Oct. l3,:1944 2,368,064 Aflarlger -Jan.f23,.1945 

